Upper Clark Fork Restoration Project

Trout Unlimited has embarked on an ambitious effort to implement large-scale habitat and flow restoration in critical spawning and rearing tributaries throughout the Upper Clark Fork. TU sees a unique opportunity to couple the high-profile main stem Superfund projects with strategic habitat and fish passage restoration work in the tributaries to recover the Clark Fork system as a whole. We intend to restore healthy populations of native westslope cutthroat trout and bull trout in the tributary/mainstem complexes where they once thrived. In doing so, we also will improve habitat conditions for the wild brown trout and rainbow trout populations that have more recently become established in the watershed.

The Clark Fork River departs Montana on its westward push to the Pacific as the state’s largest river and one of its most storied. The Clark Fork’s well known tributaries—Rock Creek , the Blackfoot and Bitterroot Rivers—triple its volume as it flows through Missoula and offer some of the more popular angling destinations in the West. Further upstream, the lesser-known Upper Clark Fork reveals an altogether different experience for anglers exploring its first hundred miles.  Smaller in size and meandering slowly through the Deer Lodge Valley, it is easily waded through most of the year. Popular only amongst the few anglers that have unlocked its secrets, its current trout population is heavily weighted toward opportunistic brown trout.

A short stroll from the riverbank onto the surrounding floodplain reveals clues to a history of ecological disaster that has left the Upper Clark Fork watershed badly in need of repair.  “Slickens” or deposits of mine tailings devoid of vegetation and covered with blue-green mineral salts dot the landscape for the first 40 miles downstream of the headwaters at the confluence of Silver Bow and Warm Springs Creeks. The metals contamination is the legacy of a copper mining and smelting boom upstream in Butte and Anaconda from the late 1800s into the middle of the last century. Flood events occasionally draw metals into the river devastating aquatic life up the food chain. In addition to the damage to the fishery from metals contamination, the Upper Clark Fork suffers from chronic dewatering as well as disconnected and degraded tributary habitat as a result of agricultural practices. Despite these insults, remnant populations of genetically pure native westslope cutthroat and bull trout continue to inhabit the upper reaches of tributaries on National Forrest lands.

TU is working with private, state and federal partners to implement cooperative fish passage, habitat, and in-stream flow improvement projects on both private and public lands.

Our goal in the Upper Clark Fork is to achieve the following:

1. Reconnect migration corridors for native westslope cutthroat and bull trout by restoring fish passage in key spawning tributaries. We will work with agricultural producers to remove or replace small irrigation dams and road culverts to reconnect critical tributaries to the Clark Fork River.
2. Restore habitat and water quality in critical spawning and rearing tributaries to benefit both native and wild trout throughout the basin. We’ll use a combination of active stream restoration, grazing management, and mine reclamation to reverse habitat degradation and increase fish numbers in tributaries and mainstem river.
3. Reconnect and restore important tributary and mainstem reaches by working with farmers and ranchers to improve irrigation efficiencies and protect more water for instream flow.

Ultimately, our goal is to restore the Clark Fork drainage to the fishy place that it was before resource extraction and agricultural development changed the landscape. We envision a restored Clark Fork basin, where fish navigate historical migration routes between pristine headwater streams and productive main stem rivers, and anglers once again have the opportunity to catch large, feisty trout throughout the watershed.

Casey Hackathorn

Rob Roberts

Casey Hackathorn, Upper Clark Fork Project Manager